Maharashtra BoardEnglish MediumSTD 11 ScienceBiologyPhotosynthesis3 Marks
Question
Crassulacean Acid Metabolism.
✓
Answer
Crassulacean Acid Metabolism $\text{(CAM).}$
$1.$ It is one more alternative pathway of carbon fixation found in desert plants.
$2.$ It was first reported in the family Crassulaceae, therefore called as $\text{CAM}($Crassulacean Acid Metabolism$).$
$3.$ In $\text{CAM}$ plants, stomata are scotoactive i.e. active during night, hence initial $CO_2$ fixation occurs in night.
$4.$ Thus, $C_4$ pathway fix $CO_2$ at night and reduce $CO_2$ in day time via the $C_3$ pathway by using $\text{NADPH}$ formed during the day.
$5. \ \text{PEP}$ caboxylase and Rubisco are present in the mesophyll cell $($no Kranz anatomy$).$
$6.$ Formation of malic acid during dark is called acidification $($phase $I).$
$7.$ Malate is stored in vacuoles during the night.
$8.$ Malate releases $CO_2$ during the day for $C_3$ pathway within the same cell is called deacidification $($phase $II).$
$9.$ Examples of $\text{CAM}$ plants: Kalanchoe, Opuntia, Aloe etc.
$10.$ The Chemical reactions of the carbon dioxide fixation and its assimilation are similar to that of $C_4$ plants.
Need a full question paper?
Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.